openlayers/ol3 — pull request #1159 by twpayne (2013-10-24 11:14:50+00:00)
Title: Export ol.extent.createEmpty function

Code by @fredj, as agreed on the mailing list. GitHub doesn't allow people to re-open pull-requests that they didn't create, and Fred is on holiday at the moment.

This replaces #1080 and #1082.